Multiphase systems for diagnosis of sickle cell disease

An aqueous multi-phase system for diagnosis of sickle cell disease is described, including two or more phase-separated phases including: a first aqueous phase including a first phase component and having a first density between about 1.025 g/cm3 and about 1.095 g/cm3; and a second aqueous phase including a second phase component and having a second density between about 1.100 g/cm3 and about 1.140 g/cm3; wherein the first density is lower than the second density; and each of the first and second phase components include at least one polymer.